<div class="container">
    <div>Hello1</div><div>Hello2</div>
</div>
<style>
    body {
        padding: 0px;
        margin: 0px;
    }
    .container {
        border: 1px solid blue;
        width: 240px;
    }
    .container > div {
        box-sizing: border-box;
        display: inline-block;
        border: 1px solid gray;
        width: 100px;
        height: 100px;
        padding: 10px;
        margin: 10px;
    }
</style>